In a food processor, combine flour, fat and salt. Pulse until the consistency of coarse sand, then slowly add water until dough forms. Wrap in plastic, form into a disc and refrigerate for an hour.

Once dough is chilled, roll out on flour surface and place in pie plate and form edges. Dock and place in the freezer for 20-30 minutes.

Meanwhile, gently whisk eggs, corn syrup, brown sugar, butter, rum, zest, vanilla and salt. Coarsely chop half of the pecans. Remove crust from freezer, place chopped nuts in pie shell. Pour filling over chopped nuts and arrange remaining nuts decoratively on top of filling. Whisk egg and water together for egg wash and brush carefully over crust and nuts. Bake for 25 minutes and check level of browning, tent with foil if necessary, bake for 30 more minutes. Allow to cool for about 5 hours.